Time Limit: Java: 1000 ms / Others: 1000 ms
Memory Limit: Java: 32768 KB / Others: 32768 KB
Given a string of characters, you may find that the word "seven" is hidden inside. For example, in the string "sesveven", five 7's are hidden:
sesveven sesveven sesveven sesveven sesveven Your task is to count the number of different 7's.
Upper-case letters are considered as the same as the lower-case letters.
For each test cases, output in a line the number of different 7's hidden inside the string. The result will be less than 2^63.